Our studies on novel small molecules inhibitors of HIV integrase have led to the identification of new potent phenanthrene diketoacid (DKA) HIV integrase inhibitors that also inhibit HIV replication in cell culture, with a selectivity index up to 10. In light of the need for more effective and less toxic anti- HIV drugs, these results appear promising and warrant follow-up optimization and preclinical studies. However, since phenanthrenes are polyaromatic hydrocarbons (PAHs) with potential carcinogenicity we propose to investigate these novel phenanthrene diketoacids for carcinogenicity potential. Our hypothesis going forward is that appropriate substitution with electron withdrawing groups can minimize mutagenicity and produce useful anti-HIV agents. This is supported by the example of the new anti-malarial drug halofantrine, a substituted phenanthrene that is effective against multidrug resistant malaria, and is neither mutagenic nor teratogenic. We thus believe that appropriate substitution of our HIV integrase inhibitory phenanthrene DKAs will make them non-mutagenic and non-carcinogenic. Thus the specific aims of this proposal are: 1) to synthesize and test the IN inhibitory activity of new phenanthrene diketoacids with multiple electron withdrawing substituents and 2) to determine the carcinogenicity potential of the phenanthrene DKAs synthesized in Specific Aim 1. We will use the Ames test for in vitro carcinogenicity testing. The success of this project will provide vital information to decide whether or not to go ahead with optimization of the potent phenanthrene DKA HIV integrase inhibitors that we discovered recently and shown to selectively inhibit HIV replication in human peripheral blood mononuclear cells. If this approach to reducing carcinogenicity is successful it will not only provide a means of eliminating carcinogenicity of the phenanthrene DKAs, but may also provide a general method for reducing the carcinogenicity of PAH containing drugs. PUBLIC HEALTH RELEVANCE: This project is aimed at investigating whether or not a novel class of potent phenanthrene diketo acid HIV integrase inhibitors that have been shown to suppress HIV viral replication in cell culture, are carcinogenic. The results of the research will determine whether to carry on with further work on optimizing this class of new anti-HIV agents towards AIDS therapeutics development.